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What happens to a hydrogen atom when ultraviolet radiation ionizes it?

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H II region Centre of the Orion Nebula (M42). Astronomers have identified some 700 young stars in this 2.5-light-year-wide area. They have also detected over 150 protoplanetary disks, or proplyds, which are believed to be embryonic solar systems that will eventually form planets. These stars and proplyds generate most of the nebula's light. This picture is a mosaic combining 45 images taken by the Hubble Space Telescope.

When a hydrogen atom is subjected to ultraviolet radiation with sufficient energy, it undergoes a process called ionization.12

Specifically, neutral hydrogen atoms are highly efficient at absorbing ionizing radiation that carries at least 13.6 electron volts of energy per photon. When a hydrogen atom absorbs such a photon, the energy is sufficient to strip the electron from the atom, resulting in a free electron and a positively charged hydrogen ion (H⁺).13

This process is fundamental to the formation and maintenance of H II regions, which are nebulae where hydrogen is primarily found in this ionized state. In these regions, the continuous presence of high-energy ultraviolet radiation from massive, hot stars keeps the hydrogen ionized, preventing it from returning to its neutral state.123